I have tested the Z-wave connectivity using two PCs (one a home-built, the other a Surface 3) using HS3 running on Windows and an Aeon ZStick Gen5, on a 1m USB extension cable and also plugged in directly.

The Z-Uno is located inside a waterproof enclosure. It is connected to a display, two relays, and a water level sensor and is reporting all the variables and controlling the relays as required. When I am close enough I receive the tank level result and can send relay on/off commands. However, when I am more than a few metres away I get no connectivity at all.

It appears to be purely range-related, as if the Z-uno is putting out a very weak signal.